Operation Sigma Sigma
The Sigma is an experimental glider developed in Britain from 1966 by a team led by Nicholas Goodhart. After disappointing performance during flight testing the Sigma was passed on to a Canadian group which carried out modifications, making the Sigma more competitive.
Design and development
Designed to compete in the 1970 World Championships, the team aimed to develop a wing that would climb well through a high lift coefficient and a large wing area, but equally had the "maximum possible reduction of area for cruise at low lift coefficients". At the same time for the minimum possible drag they aimed for "extensive" laminar flow. To achieve this they employed flaps that would alter both wing area and wing camber. Based on analysis of the nature of thermals encountered in cross-country flying, they reasoned that by having a slow turning circle, their sailplane could stay close to the central (and strongest) part of the thermal and gain maximum benefit.
Its unusual feature is its ability to vary its wing area using Fowler flaps. It had been tried before by the Hannover Akaflieg in 1938 with their AFH-4, the South African Beatty-Johl BJ-2 Assegai and the SZD Zefir gliders.
Sigma (duo)
Sigma is an English drum and bass duo consisting of Cameron Edwards and Joe Lenzie. They met at Leeds University at drum and bass nights. Their 2010 collaboration with DJ Fresh, "Lassitude", peaked at number 98 on the UK Singles Chart. Their single "Nobody to Love" topped the UK Singles Chart, becoming their first UK number one. Follow-up single "Changing", featuring Paloma Faith, also got to number one.
Career
Formation
Lenzie and Edwards met in 2006 at Leeds University; Cameron was working in local record store Tribe Records and with Echo Location's Obi running local night Event Horizon, while Lenzie was DJing hip-hop and warming up Event Horizon for such acts as Rahzel and Grandmaster Flash. Once they had finished in Leeds, they relocated to London and became a three-piece with Edwards' school friend Ben Mauerhoff, being signed under DJ Fresh's Breakbeat Kaos. After a while, long distances took their toll – Edwards and Mauerhoff were based in Surrey, whereas Lenzie was based in Harpenden, Hertfordshire and they couldn't get three people into the Harpenden studio – and Mauerhoff left. In December 2008 they formed their own record label, Life Recordings (so called because, according to Lenzie, the industry demanded that it be their life). Its inaugural release was a VIP mix of their early Bingo Beats single "El Presidente".
Sigma baryon
The Sigma baryons are a family of subatomic hadron particles which have a +2, +1 or −1 elementary charge or are neutral. They are baryons containing three quarks: two up and/or down quarks, and one third quark, which can be either a strange (symbols Σ+, Σ0, Σ−), a charm (symbols Σ++
c, Σ+
c, Σ0
c), a bottom (symbols Σ+
b, Σ0
b, Σ−
b) or a top (symbols Σ++
t, Σ+
t, Σ0
t) quark. However, the top Sigmas are not expected to be observed as the Standard Model predicts the mean lifetime of top quarks to be roughly 6975500000000000000♠5×10−25 s. This is about 20 times shorter than the timescale for strong interactions, and therefore it does not form hadrons.
List
The symbols encountered in these lists are: I (isospin), J (total angular momentum), P (parity), u (up quark), d (down quark), s (strange quark), c (charm quark), t (top quark), b (bottom quark), Q (charge), B (baryon number), S (strangeness), C (charmness), B′ (bottomness), T (topness), as well as other subatomic particles (hover for name).
Hex (comics)
Hex, in comics, may refer to:
It may also refer to:
See also
References
Hex (climbing)
A hex is an item of rock climbing equipment used to protect climbers from injury during a fall. They are intended to be wedged into a crack or other opening in the rock, and do not require a hammer to place. They were developed as an alternative to pitons, which are hammered into cracks and are more prone to damage the rock. Most commonly, a carabiner will be used to join the hex to the climbing rope by means of a loop of webbing, cord or a cable which is part of the hex.
Hexes are a type of nut, a hollow eccentric hexagonal prism with tapered ends, usually threaded with webbing, a swaged cable, or a cord. They are manufactured by several firms, with a range of sizes varying from about 10–100 millimetres (0.4–4 in) wide. Climbers select a range of sizes to use on a specific climb based on the characteristics of the cracks in the rock encountered on that particular climb. Sides may be straight or curved although the functioning principles remain the same no matter which shape is selected; the lack of sharp corners on curved models may make them easier to remove from the rock.
Hex (Discworld)
Hex is a fictional computer featuring in the Discworld novels by Terry Pratchett. First appearing in Soul Music, Hex is an elaborate, magic-powered and self-building computer (not unlike the 'shamble', a kind of magical device used by the Wizards of the Discworld) and is housed in the basement of the High Energy Magic Building at the Unseen University (UU) in the twin city of Ankh-Morpork.
Hex is a computer unlike any other the Disc has ever seen, which is not particularly exceptional since previously all other "computers" on the Disc had consisted of druidic stone circles. Programmed via 'Softlore', Hex runs and evolves under the watchful eyes of wizard Ponder Stibbons, who becomes the de facto IT manager at UU because he's the only one who understands what he's talking about.
Origins and evolution
Hex has its origins in a device that briefly appeared in Soul Music, created by Ponder Stibbons and some student Wizards in the High Energy Magic building. In this form it was simply a complex network of glass tubes, containing ants. The wizards could then use punched cards to control which tubes the ants could crawl through, enabling it to perform simple mathematical functions.
Podcasts:
